Variability is a signature feature of young stars. Among the well known light curve phenomena
are periodic variations attributed to surface spots and irregular changes associated with
accretion or circumstellar disk material. While decades of photometric monitoring have
provided a framework for classifying young star variability, we still know surprisingly little
about its underlying mechanisms and connections to the surrounding disks. In the past few
years, dedicated photometric monitoring campaigns from the ground and space have
revolutionized our view of young stars in the time domain. I will present a selection of
optical and infrared time series from several recent campaigns, highlighting the Coordinated
Synoptic Investigation of NGC 2264 ("CSI 2264")-- a joint 30-day effort with the Spitzer,
CoRoT, and MOST telescopes. The extraordinary photometric precision, high cadence, and long
time baseline of these observations is now enabling correlation of variability properties at
very different wavelengths, corresponding to locations from the stellar surface to the inner
0.1 AU of the disk. I will present some results of the CSI 2264 program, including new
classes of optical/infrared behavior, as well as light curves that defy explanation. Further
efforts to tie observed variability features to physical models will provide insights
into the inner disk environment at a time when planet formation may be underway.